1. Field of the Invention
The subject invention relates to bearing and particularly to radial bearings used in directional or steerable earth boring applications.
2. Description of Related Art
Radial bearings for use in earth boring applications such as oil well drilling are generally well-known and particularly known for use in down hole drilling motors. Radial bearings most recently have been fabricated using tungsten carbide materials, such as tungsten carbide buttons or tungsten carbide chips bonded to a bearing sleeve or drive shaft.
For some time, radial bearings used in directional or steerable drilling applications have exhibited excessive wear at the upper and lower extremities of the radial bearing surface. Such wear arises because the drive shaft to which such bearings are attached is subjected to bending during directional or steerable drilling. While drive shafts used in such can accomodate such bending, the cooperating radial bearings cannot.